Comparative Analysis Over Tribology Characterization of TiAlN and TiAlSiN PVD Coating On Plasma Nitride Alloy 20

The nickel-iron-chromium (alloy 20) is enriching by hybrid surface treatment through plasma nitride (PN) and physical vapor deposition (PVD) process. The plasma nitriding process takes 12 hours at 500°C. Potentiodynamic testing is used to characterize the corrosion performance of the treated material, followed by morphological analysis of the exposed surface; XRD, EDX, SEM, hardness, and tensile testing are used to investigate appropriate coating properties. Plasma nitride and hybrid PVD nickel-iron-chromium alloys exhibit perlite (γ + α ’) phases and martensite (γ + α) phases, respectively. The martensite microstructure ensures superior tensile strength and hardness. The pin-on-disc tribometer test proposes to analyze friction and hard-faced behavior in the dry sliding position. The inclusion of Si improves the adherent oxide film, resulting in a low wear rate in TiAlSiN alloy 20. Due to the presence of the passive film, TiAlSiN alloy 20 exposes the most passive region to attain better corrosion resistance.

Hardness and Microstructure Homogeneity of Pure Copper and Iron-Chromium Alloy Processed by Severe Plastic Deformation

Hardness and microstructure homogeneity of pure copper and iron-chromium alloy processed by severe plastic deformation (SPD) were investigated in grain refinement. Equal channel angular pressing (ECAP) is one of the well-known techniques of the SPD technique due to their up-scale ability and other methods. SPD was applied to pure copper and iron-chromium alloy at comparable temperatures up to four passes. The microstructure and microhardness were observed and measured in the transverse plane for each billet. The homogeneity observation was carried out from the sub-surface until in the middle of the billet. The result showed that the deformed structure appeared adequately after the first pass and had a higher hardness level. The first pass showed a higher inhomogeneity factor than the fourth pass due to the homogeneity microstructure. The hardness also showed homogeneous value along the transverse plane, and it was concluded that ECAP could achieve complete homogeneity in grain refinement

Microstructure and Strain Hardening Behaviour of Iron Chromium Alloy Subjected by Severe Plastic Deformation

Microstructure and strain hardening behaviour of iron-chromium alloy subjected to severe plastic deformation (SPD) have been investigated in grain refinement and deformation routes. Equal channel angular pressing (ECAP) was used in this SPD technique due to their un-change dimension billet. The purpose of this research is to investigate the structure and the strain hardening of iron chromium alloy subjected by ECAP process. The ECAP process was carried by routes A, Bc and C up to four passes at 423 K temperature. The strength of the material was measured by tensile testing with 3 mm gauge length, and the strain hardening behaviour was investigated based on the true stress-strain curve. The effect of the deformation route on microstructure and texture was observed by electron backscattered diffraction (EBSD) analysis at the normal, transverse and rolling direction. The result showed that route Bc showed the highest strength and ductility of the ECAP processed material compare to other routes due to their 90 degrees rotation of each ECAP passes number. The increased strength of materials was also associated with grain refinement and accumulation dislocation. It concluded that the ECAP process by route Bc could be used for further material treatment and application for industrial purposes.

Effect of Preliminary Deformation on Microstructure and Texture of Iron-Chromium Alloy Prepared by Severe Plastic Deformation

The effect of preliminary deformation on the microstructure and texture of iron-chromium alloy prepared by severe plastic deformation (SPD) has been investigated in grain refinement and inhomogeneity structure. Equal channel angular pressing (ECAP) is a well-known SPD process that uses a die channel with a sharp angle. The texture and misorientation map of ECAP processed material was observed electron backscattered diffraction (EBSD) analysis, providing information on structure evolution. The observation was done in the transverse plane from the middle to the sub-surface. The data logger also records the pressure of the ECAP process. The result showed that the sub-surface has a more deformed structure than the middle due to the die channel's sharp angle and shear direction. The texture exhibited a random orientation after the first pass ECAP process. The stacking fault energy and accumulation dislocation are also associated with this process. Several shear bands can be seen clearly, which is parallel to the shear direction. It concluded that the preliminary deformation by ECAP was effective to promote grain refinement due to their high equivalent strain

NIPPON YAKIN NAS 800

Nippon Yakin NAS 800 is an austenitic nickel-iron-chromium alloy that exhibits high strength and excellent resistance to oxidation and carburization at high temperatures. It also offers excellent corrosion resistance in many aqueous environments. It is normally employed in service temperatures up to and including 600 °C (1100 °F). This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: Ni-773. Producer or source: Nippon Yakin Kogyo Co., Ltd.

Effect of strain energy on the grain growth behaviour of ultrafine-grained iron-chromium alloy by equal channel angular pressing

The grain growth of an ultrafine-grained iron-chromium alloy has been investigated focusing on the early stage of restoration of strain. Ultrafine-grained (UFG) material has been prepared by equal channel angular pressing (ECAP) up to eight passes via route Bc. The post-ECAP annealing process was completed from 473 until 1373 K for one hour. The microstructure and hardness were then analyzed by electron back-scattering diffraction, transmission electron microscope, X-ray diffractometer and microhardness. The hardness after post-ECAP annealing exhibited the typical three-stages softening. Namely, the hardness remained stable after the annealing temperature up to 698 K and then declined significantly until the temperature of 973 K. Finally, hardness remained stable again at a higher temperature. In the second stage, grains grew uniformly, which differ from the typical nucleation-and-growth mode of discontinuous recrystallization. It was found by X-ray line broadening analysis that strain was released in the early stage prior to the significant softening stage. It was suggested that the homogeneous grain growth was led by the uniform grain distribution with a high angle grain boundaries fraction.